I wish you good luck in your endeavor's VA...

This is a trick I use when field judging a deer's antler inches quickly.

Start with 90" (if it's a real good buck at least 3.5 yrs.) then add tine length of each tine you see (a rough guess).. next follow it up with the inside spread estimate.

It may sound stupid.. but it's quick.. and usually pretty accurate. If anything.. I'm usually under scoring the buck more than anything. But it's quick and can be done with bino's in well under a minute. For those buck's that don't give you that long.. shoot first and ask questions later.